Lead and pacing characteristics
Patients underwent 89 epicardial lead implantations, and their function was studied during 2015-2018. Indication for pacemaker implantation mostly consisted of atrioventricular block (52.81%) and CCHB (19.10%). The most prevalent symptom before pace implementation was dyspnea on exertion (59.79%), followed by syncope (8.25%), and palpitation (7.22%) (see Supplementary Table 2 and 3).
Of total implants, 59 (66.29 %) were unipolar non-steroid-eluting type, and others were bipolar steroid-eluting (33.71 %). Most of the leads were only located on the ventricles (68 leads; 88.31%), while, nine leads were implanted on both atrium and ventricle. Left ventricular leads were more prevalent (76.62%). There was no significant difference between the unipolar non-steroid-eluting and bipolar steroid-eluting leads regarding the cavity where they were implanted on (p-value=0.35). VVR and VVIR were the most prevalent pacing modes either for unipolar non-steroid-eluting or bipolar steroid-eluting leads (68.49% of total leads). There was no significant difference between pacing modes of the unipolar non-steroid-eluting and bipolar steroid-eluting leads (Table 2). QRS duration and LVEF at lead implantation time were not significantly different between unipolar non-steroid-eluting and bipolar steroid-eluting leads (Table 2 and Table 3).